The present disclosure relates to a display unit having touch detection function, and particularly relates to a display unit with touch detection function of detecting a touch event based on a change in capacitance due to an external proximity object, and an electronic unit having such the display unit with a touch detection function.
Recently, a display unit has been notified, where a touch detection device, a so-called touch panel, is mounted on a display device such as liquid crystal display device, or the touch panel is integrated with the display device, and various button images or the like are displayed on the display device instead of common mechanical buttons, enabling information input. Such a display unit having the touch panel needs no input device such as a keyboard, a mouse, and a keypad and therefore tends to be expansively used not only for computers but also for handheld information terminals such as a mobile phone.
A type of the touch detection device includes several types such as an optical type and a resistance type. In particular, a capacitance-type touch detection device has been promising as a device allowing low power consumption with a relatively simple structure. For example, Japanese Unexamined Patent Application Publication No. 2009-244958 (JP-A-2009-244958) proposes a display unit where an common-electrode originally provided for display of the display unit is used also as one of a pair of electrodes for a touch sensor, and the other electrode (touch detection electrode) is disposed to intersect the common electrode. Capacitance is formed between the common electrode and the touch detection electrode, and the capacitance is changed in response to an external proximity object. The display unit uses such change in capacitance to detect the external proximity object by analyzing a touch detection signal shown on the touch detection electrode when a drive signal is applied to the common electrode.